fix: atomic writes to preferences COMPASS-7270 COMPASS-7269 (#4920)

Author: mabaasit

package-lock.json

@@ -136,6 +136,23 @@ describe('storage', function () {
       ).to.deep.equal(getDefaultPreferences());
     });
 
+    it('when invalid json is stored, it sets the defaults', async function () {
+      const storage = new StoragePreferences(tmpDir);
+
+      const preferencesFile = getPreferencesFile(tmpDir);
+      await fs.mkdir(getPreferencesFolder(tmpDir));
+      await fs.writeFile(preferencesFile, '{}}', 'utf-8');
+
+      // Ensure it exists
+      expect(async () => await fs.access(preferencesFile)).to.not.throw;
+
+      await storage.setup();
+
+      expect(
+        JSON.parse((await fs.readFile(preferencesFile)).toString())
+      ).to.deep.equal(getDefaultPreferences());
+    });
+
     it('updates preferences', async function () {
       const storage = new StoragePreferences(tmpDir);
       await storage.setup();

packages/compass-preferences-model/src/storage.spec.ts

@@ -74,11 +74,15 @@ export class StoragePreferences extends BasePreferencesStorage {
     try {
       this.preferences = await this.readPreferences();
     } catch (e) {
-      if ((e as any).code !== 'ENOENT') {
-        throw e;
+      if (
+        (e as any).code === 'ENOENT' || // First time user
+        e instanceof SyntaxError // Invalid json
+      ) {
+        // Create the file for the first time
+        await this.userData.write(this.file, this.defaultPreferences);
+        return;
       }
-      // Create the file for the first time
-      await this.userData.write(this.file, this.defaultPreferences);
+      throw e;
     }
   }
 

packages/compass-preferences-model/src/storage.ts

@@ -58,6 +58,7 @@
     "@types/chai": "^4.2.21",
     "@types/mocha": "^9.0.0",
     "@types/sinon-chai": "^3.2.5",
+    "@types/write-file-atomic": "^4.0.1",
     "chai": "^4.3.6",
     "depcheck": "^1.4.1",
     "eslint": "^7.25.0",
@@ -67,6 +68,7 @@
     "prettier": "^2.7.1",
     "sinon": "^9.2.3",
     "typescript": "^5.0.4",
+    "write-file-atomic": "^5.0.1",
     "zod": "^3.22.2"
   }
 }

packages/compass-user-data/package.json

@@ -4,6 +4,7 @@ import path from 'path';
 import { createLoggerAndTelemetry } from '@mongodb-js/compass-logging';
 import { getStoragePath } from '@mongodb-js/compass-utils';
 import type { z } from 'zod';
+import writeFile from 'write-file-atomic';
 
 const { log, mongoLogId } = createLoggerAndTelemetry('COMPASS-USER-STORAGE');
 
@@ -172,7 +173,7 @@ export class UserData<T extends z.Schema> {
     const filepath = this.getFileName(id);
     const absolutePath = await this.getFileAbsolutePath(filepath);
     try {
-      await fs.writeFile(absolutePath, this.serialize(content), {
+      await writeFile(absolutePath, this.serialize(content), {
         encoding: 'utf-8',
       });
       return true;

packages/compass-user-data/src/user-data.ts

@@ -108,7 +108,13 @@ async function main(): Promise<void> {
     });
   }
 
-  await CompassApplication.init(mode, globalPreferences);
+  try {
+    await CompassApplication.init(mode, globalPreferences);
+  } catch (e) {
+    await handleUncaughtException(e as Error);
+    await CompassApplication.runExitHandlers().finally(() => app.exit(1));
+    return;
+  }
 
   if (mode === 'CLI') {
     let exitCode = 0;